1. Field of the Invention
The present invention relates to a liquid supplier, and more particularly to a constant flow device that supplies a constant flow of a liquid.
2. Description of Related Art
With reference to FIG. 5, a conventional constant flow liquid supplier in accordance with the prior art comprises a tank (90) and an adjustable control unit (94). The tank (90) including a supply tube (91) and a discharge tube (92) mounted near the bottom of the tank (90). A remotely operated valve (not numbered) is mounted in the supply tube (91) to selectively open the supply tube (91). A discharge valve (not numbered) is mounted in the outlet tube (92) to control the liquid discharged. The adjustable control unit (94) is electrically connected to the remotely operated valve and has a float ball (93) floating on the surface of the liquid in the tank (90). The float ball (93) is connected to the control unit (94) by a wire (not numbered) so that the float ball (93) pulls the control unit (94) when the surface of the liquid drops to a suitable level. The force transmitted to the control unit (94) is transformed to a signal to the remotely controlled valve to open the supply tube (91)
However, the conventional constant flow liquid supplier has the following disadvantages that need to be improved.
1. Complex and high cost: The remotely controlled valve, the discharge valve and the control unit (94) are necessary elements of the conventional constant flow liquid supplier so that the structure of the conventional constant flow liquid supplier is complex and has a high cost.
2. Unstable and not precise: The instantaneous discharge of the conventional liquid supplier varies depending on the liquid level because a high pressure is applied to the discharge valve when the liquid surface is high in the tank (90) and a lower pressure is applied when the liquid surface comes down. The pressure of the liquid in the tank will impact the preciseness of the discharge valve.
3. Waste power: Electricity is necessary to the control unit (94) so that the conventional constant flow liquid supplier cannot operate when the electric power is interrupted.
4. Easily fail: The conventional constant flow liquid supplier does not work when any one of the remotely controlled valve, the discharge valve or the control unit (94) is broken.
The present invention has arisen to mitigate and/or obviate the disadvantages of the conventional constant flow liquid supplier.
The main objective of the present invention is to provide an improved constant flow liquid supplier that uses a floating siphon to control the discharge.
To achieve the objective, the constant flow liquid supplier in accordance with the present invention comprises a body having a cavity defined to contain liquid. An inlet assembly floats on the liquid surface and selectively opens the inlet of the constant flow liquid supplier. An outlet assembly floats on the liquid surface and has an inverted U-shaped siphon. The siphon has an inlet in the cavity and an outlet out of the body. The outlet is lower than the inlet. Based on the principles of operation of a siphon and the structure of the present invention, the liquid in the body flows out of the outlet of the siphon at a constant rate when the siphon is discharging liquid.
Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.